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+# AGENTS.md
+
+## Scope
+
+Build and maintain Phast as a deliberately small Python + Prefab + MCP application platform.
+
+## Product model
+
+- `my.phast.app` is the owner control plane.
+- Each `app.phast.app` is independently useful and independently connectable.
+- `/` is the human Prefab UI by default.
+- `/mcp` is the agent interface by default.
+- A Prephab is a cloneable Python + Prefab + MCP application shape.
+
+## Working rules
+
+- Prefer boring, explicit Python over framework sprawl.
+- Keep one source of truth for app state and capabilities.
+- Do not fake auth or security; mark seams explicitly.
+- No delete path until it is deliberately designed.
+- Commit small coherent changes to `main` and leave the system simpler.